The present invention relates to orthopaedic supports and in particular, relates to a composite substrate for orthopaedic supports having improved breathability.
Neoprene layers have been used for orthopaedic supports as they have the ability to stretch and are initially relatively comfortable. Typically, the neoprene layer has a cloth fibre layer on the surface thereof to improve the comfort. Unfortunately, neoprene or other closed cell foam layers are not breathable and tend to retain heat about the body part. Initial heat retention can be advantageous as it warms the particular body part, however, over an extended period of time, it leads to discomfort, possible skin rashes, and is not desirable. These poor operating characteristics often contribute to the orthopaedic support not being used.
It has been known to use a closed cell foam structure with a breathable fabric either side to improve the characteristics of the composite material. Unfortunately, the closed cell foam acts as an excellent thermal insulation and excess heat and moisture typically occurs.
U.S. Pat. No. 5,620,771 discloses a specialized orthopaedic substrate layer which has a series of pin holes with each pin hole acting as a pressure release valve which vents when sufficient pressure is achieved. This structure also tends to maintain moisture and maintain heat.
The present invention seeks to overcome the shortcomings described above.
An orthopaedic support according to the present invention comprises a composite substrate for fastening about a body part with the composite substrate comprising a foam cellular layer with a series of interconnecting channels in one side thereof. A series of holes extend through the foam cellular layer and provide improved venting and air circulation. The composite substrate includes a breathable layer covering the one side of the foam cellular layer and this breathable layer cooperates with the channels and the series of holes to provide air circulation through the composite substrate and through the channels.
It has been found that the composite substrate as described above provides improved air circulation through the substrate. The additional movement of the body part associated with the orthopaedic support expands or compresses the composite substrate and provide a pumping action further promoting air exchange through the substrate.
According to a further aspect of the invention, the composite substrate includes a breathable fabric on an exterior surface of the closed cell foam layer opposite the breathable layer.
According to yet a further aspect of the invention, the orthopaedic support is reversible to alter the heat retention characteristic of the orthopaedic support.
In yet a further aspect of the invention, the channels are selected from longitudinal channels, lateral channels and diagonal channels.
In yet a further aspect of the invention, the longitudinal channels, lateral channels and diagonal channels intercept with some of the series of holes through the foam cellular layer.
In yet a further aspect of the invention, the foam cellular layer is made of neoprene.
In yet a further aspect of the invention, the channels occupy less than 25 percent of the one side of the foam cellular layer.